#include <bits/stdc++.h>
using namespace std;

const int MAXN = 100010;

ifstream fin("arbint.in");
ofstream fout("arbint.out");

int n, m, arb[3 * MAXN], x, y, a, b, val, pos, tip, maxim;

void update(int node, int l, int r)
{
    if (l == r)
    {
        arb[node] = val;
        return;
    }
    int m = (l + r) / 2;
    if (pos <= m)
        update(2 * node, l, m);
    else
        update(2 * node + 1, m + 1, r);
    arb[node] = max(arb[2 * node], arb[2 * node + 1]);
}

void query(int node, int l, int r)
{
    if (l >= x && r <= y)
    {
        maxim = max(maxim, arb[node]);
        return;
    }
    int m = (l + r) / 2;
    if (x <= m)
        query(2 * node, l, m);
    if (m < y)
        query(2 * node + 1, m + 1, r);
}

int main()
{
    fin >> n >> m;
    for (int i = 1; i <= n; ++i)
    {
        fin >> x;
        val = x;
        pos = i;
        update(1, 1, n);
    }
    for (; m; --m)
    {
        fin >> tip >> a >> b;
        if (tip == 1)
        {
            pos = a;
            val = b;
            update(1, 1, n);
        }
        else
        {
            x = a;
            y = b;
            maxim = -1;
            query(1, 1, n);
            fout << maxim << '\n';
        }
    }
    return 0;
}